The factory used to style bolts for the hold down. Hard to say when the switchover was I've seen many 69's with a blunt tip like Phils and I've seen many with a pointed tip, here's some pictures of originals. The original blunt tip headmarkings are LF + SEMS. Other original headmarkings would be F, Anchor, E, Anchor over Tee, Rbw, E in circles. These are tough to find in good shape there almost always pitted badly from the battery acid.
The second style bolt that was used had a pointed tip, both the pointed and blunt tip bolts measure 1 inch long from under the washer to the end of the bolt. Head markings I've seen for those are, ELH, EL, RBW + B&H.